Extended address space capability for an industrial protocol

ABSTRACT

Systems and methods are provided for communicating with control objects according to a singular and unified address space. In one aspect, an industrial communications system is provided. The system includes a global address protocol that can be employed to communicate with local or remote networks. An industrial protocol is adapted to interface with the global address protocol, where a network component communicates with one or more control components via the industrial protocol and in accordance with an address supplied by the global address protocol.

TECHNICAL FIELD

The subject invention relates generally to industrial control systems,and more particularly to systems and methods that provide a unifiedaddressing space in an industrial protocol to enable communicationsacross networks with a singular addressing mode.

BACKGROUND

Industrial controllers are special-purpose computers utilized forcontrolling industrial processes, manufacturing equipment, and otherfactory automation, such as data collection or networked systems. At thecore of the industrial control system, is a logic processor such as aProgrammable Logic Controller (PLC) or PC-based controller. ProgrammableLogic Controllers for instance, are programmed by systems designers tooperate manufacturing processes via user-designed logic programs or userprograms. The user programs are stored in memory and generally executedby the PLC in a sequential manner although instruction jumping, loopingand interrupt routines, for example, are also common. Associated withthe user program are a plurality of memory elements or variables thatprovide dynamics to PLC operations and programs. Differences in PLCs aretypically dependent on the number of Input/Output (I/O) they canprocess, amount of memory, number and type of instructions, and speed ofthe PLC central processing unit (CPU).

In recent years, there has been a growing need to integrate industrialcontrol systems across a plurality of different types of networks. Onepopular network that is now common in industrial environments isEthernet. This network is often applied at medium or higher levels of abusiness network where components such as bridges, routers or othertypes of modules supply connectivity and communications to lower controlnetworks in the factory. Due to the limited number of Internet Protocol(IP) addresses in the Ethernet IPV4 protocol, most industrial Ethernetinterfaces only support a single IP address and use some other means toaddress interfaces within the industrial system. This usually requires aclient system to support multiple addressing modes to select a singledevice, interface or object which adds complexity and cost to theoverall system.

SUMMARY

The following presents a simplified summary in order to provide a basicunderstanding of some aspects described herein. This summary is not anextensive overview nor is intended to identify key/critical elements orto delineate the scope of the various aspects described herein. Its solepurpose is to present some concepts in a simplified form as a prelude tothe more detailed description that is presented later.

A flat and singular address space is integrated with an industrialcontrol protocol to facilitate communications in an industrialautomation environment. In one example of such address space, IPV6 orother singular address space is adapted for industrial controladdressing. This enables mapping of individual objects, interfaces anddevices to a unique IPV6 address, for example. Using this technique of asingle addressing mode, the large IPV6 addressing space (or other globaladdressing space) can be used to address each object in the industrialsystem. Thus, in one example, an Ethernet interface card can respond toeach object within its scope and contain the routing information toenable a message to reach the object generally using only the IPV6address.

Each of the respective addresses can be mapped using a Domain NameService (DNS) server to a user assigned name in order that each objectcan be addressed by a user assigned name. These names can be arrangedinto a hierarchy that corresponds to the user's problem or physicaldomain, for example. In one aspect, the DNS server or other directoryservice can map hierarchical names to an IPV6 address (or other globaladdressing scheme) and the industrial Ethernet interface would map theIPV6 address to an individual object in the industrial automationsystem. Each object could have multiple addresses, one to indicate itsphysical location and another to indicate its function in the logicaldescription of the user's problem.

To the accomplishment of the foregoing and related ends, certainillustrative aspects are described herein in connection with thefollowing description and the annexed drawings. These aspects areindicative of various ways which can be practiced, all of which areintended to be covered herein. Other advantages and novel features maybecome apparent from the following detailed description when consideredin conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram illustrating industrial controlsystem network communications.

FIG. 2 is a diagram illustrating an example network and addressingstructure.

FIG. 3 is a diagram illustrating communications according to an EthernetIPV6 protocol.

FIG. 4 is a diagram illustrating a communications according to anEthernet IPV6 protocol and a domain name service addressing scheme.

FIG. 5 is a diagram illustrating an alternative network communicationsystem.

FIG. 6 is a flow diagram illustrating a communications process for ssingular address space.

FIG. 7 is a diagram illustrating an example Ethernet IPV6 data packetfor communications with an industrial control system.

FIG. 8 is a diagram illustrating example Ethernet IPV6 addressing modes.

DETAILED DESCRIPTION

Systems and methods are provided for communicating with control objectsaccording to a singular and unified address space. In this manner,control objects can be addressed according to a single protocol whichmitigates configuration and design complexities of communicating throughmultiple network devices supporting multiple address spaces. In oneaspect, an industrial communications system is provided. The systemincludes a global address protocol that can be employed to communicatewith local or remote networks. An industrial protocol is adapted tointerface with the global address protocol, where a network componentcommunicates with one or more control components via the industrialprotocol and in accordance with an address supplied by the globaladdress protocol. In one example, the global address protocol caninclude an IPV6 protocol.

It is noted that as used in this application, terms such as “component,”“protocol,” “interface,” and the like are intended to refer to acomputer-related entity, either hardware, a combination of hardware andsoftware, software, or software in execution as applied to an automationsystem for industrial control. For example, a component may be, but isnot limited to being, a process running on a processor, a processor, anobject, an executable, a thread of execution, a program and a computer.By way of illustration, both an application running on a server and theserver can be components. One or more components may reside within aprocess and/or thread of execution and a component may be localized onone computer and/or distributed between two or more computers,industrial controllers, and/or modules communicating therewith.

Referring initially to FIG. 1, a system 100 illustrates industrialcontrol communications and network protocols. The system 100 includes aplurality of control objects 110 (or components) that communicate to oneor more one or more controllers and/or communications modules 120 via anindustrial protocol. The control objects 110 are assigned a networkaddress according to a flat and singular address convention or spaceillustrated at 130. One or more networks are employed to interface withthe singular address space 130 and interact with the control objectsaccording to address supplied by the space 130. Network interfaces 120can reside on a controller, communications module, and/or as a separateentity. A discovery component 150 can be employed to locate controlobjects 110, controllers 120, or networks 140 employing logical namingconventions versus explicit addresses. It is to be appreciated that acombination of explicit addressing and/or logical addressing can beemployed to communicate with the controllers 120 and respective controlobjects 110.

In general, the singular address space 130 can be integrated with anindustrial control protocol to facilitate communications in the system100. In one example of such address space, IPV6 (e.g., Ethernet) isadapted for industrial control addressing. This enables mapping ofindividual control objects 110, networks 140 and devices 120 to a uniqueIPV6 address. Using this single addressing mode, the large, flat IPV6addressing space can be used to address each control object 110 in theindustrial system 100. An interface card at 120 can respond to eachcontrol object 110 within its scope and contain the routing informationto enable a message to reach the object generally using only the globaladdress supplied by the space 130. It is to be appreciated, thatsubstantially any higher level global network protocol that allowsaddresses to be migrated and resolve lower level control objects isconsidered within the scope provided herein.

Generally, each of the respective addresses 130 can be mapped using thediscovery component 150 (e.g., a Domain Name Service (DNS) server) to auser assigned name in order that each object 110 can be addressed by auser assigned name. These names can be arranged into a hierarchy thatcorresponds to the user's problem or physical domain, for example. Inone aspect, the DNS server or discovery component 150 can maphierarchical names to an address 130 and the industrial interface 120can map the address to an individual object 110 in the industrialautomation system 100. It is noted that each control object 110 can havemultiple addresses, one to indicate its physical location and another toindicate its function in a logical description of the user's factory orenvironment.

Before proceeding, it is noted that the system 100 can include variouscomputer or network components such as servers, clients, communicationsmodules, mobile computers, wireless components, and so forth which arecapable of interacting across the networks 140. Similarly, the term PLCor controller as used herein can include functionality that can beshared across multiple components, systems, and/or networks. Forexample, one or more PLCs at 120 can communicate and cooperate withvarious network devices across the networks 140. This can includesubstantially any type of control, communications module, computer, I/Odevice, Human Machine Interface (HMI) that communicate via the networkwhich includes control, automation, and/or public networks. The PLC orcontroller/communication module 120 can also communicate to and controlvarious other devices or control objects 110 such as Input/Outputmodules including Analog, Digital, Programmed/Intelligent I/O modules,other programmable controllers, communications modules, softwarecomponents, and the like. 100221 The networks in the system 100 caninclude public networks such as the Internet, Intranets, and automationnetworks such as Common Industrial Protocol (CIP) networks includingDeviceNet and ControlNet. Other networks include Ethernet, DH/DH+,Remote I/O, Fieldbus, Modbus, Profibus, wireless networks, serialprotocols, and so forth. In addition, the network devices can includevarious possibilities (hardware and/or software components). Theseinclude components such as switches with virtual local area network(VLAN) capability, LANs, WANs, proxies, gateways, routers, firewalls,virtual private network (VPN) devices, servers, clients, computers,configuration tools, monitoring tools, and/or other devices.

Referring now to FIG. 2, an example network structure 200 isillustrated. The top of the structure 200 is represented by a globaladdress space 210 than can be employed to address devices at lowerlevels of an enterprise and across control networks. From theseaddresses 210, one or more network interfaces can be provided at 220.These interfaces 220 can apply the addresses 210 to one or more controllayers 230 that are operatively coupled to the interfaces. It is noted,that the network interface 220 and control layer 230 can includemultiple dimensions supporting a plurality of configurations. Forinstance, the network interfaces can include multiple layers in avertical direction on the diagram, where each respective layer is adiffering type of industrial network. Similarly, at any given networkinterface layer 220, a plurality of network interface components ordevices could exist at that layer to interface to a respective controllayer 230. Along with the network interface having vertical andhorizontal dimensions, the control layer can similarly have multipledimensions, where a plurality of control components can exist on anygiven control layer 230 and/or a plurality of control layers can beconfigured for communications with the global address space 210.

As noted above, IPV6 protocol or other singular addressing mode can beemployed as the protocol for the global address space 210. Lower leveldevices at the control layers 230 can be located and communicated withby assigning such devices addresses from the global address space. Inone specific example, a control message may be generated using IPV6protocol where the message originates from Europe. The message isdesignated and addressed to a controller operating on a control layer230 in the U.S. The controller may be operating on a Common IndustrialProtocol (CIP) Network or a device network, yet be assigned an absoluteaddress from the global address space 210. Thus, the remote messageoriginating from Europe sends a control message to the device on thefactory network as if the device were operating in the global addressspace. As can be appreciated, a plurality of communications and messagescan be provided from local and/or remote networking sources. To continuethe example, a discovery component (not shown) such as a DNS can beemployed to provide logical naming conventions for control layer devicesor components 230 to be determined from the global address space.

Turning to FIG. 3, an example system 300 illustrates communicationsaccording to an Ethernet IPV6 protocol. The system 300 shows anindustrial Ethernet network at 310 where an Ethernet interface 320communicates with the network. As noted above, there can be a pluralityof such interfaces communicating with the network 320. In this example,two IPV6 addresses are assigned at 324 and 330 respectively. Below thelayer at 320, resides another industrial network 340 which can besubstantially any type of network. In this example, two control objects350 and 360 respectively are also assigned with an IPV6 address. Thus,these control objects 350 and 360 can be addressed on their localindustrial networks 340 (e.g., CIP protocol, ModBus, ProfiNet) accordingto an address that is assigned from the address space in the Ethernetdomain 310. In this manner, the Ethernet interface 320 can be designedfor a single addressing scheme and without having to convert addressesto local industrial addressing schemes at 340. As can be appreciated, aplurality of control objects can exist at the network layer 340. Also,more than one layer 340 can be provided that supports IPV6 addressingwhere some layers are nested below other layers.

It is noted that IPv6 addresses can be assigned to specific objectswithin a CIP protocol, for example. The IPv6 addresses can be assignedto particular control functions beyond CIP protocols and can be assignedto any type of entity or construct in the control system, e.g., tags(named data), routines, entities that are associated with a plant orenterprise model, and so forth. When assigning IPv6 addresses to objectswithin devices, there are different models that can be employed. Thesecan include where a device has a single instance of a CIP (or other)protocol stack, with a single application addressing space. MultipleIPv6 addresses could be managed at a level above the industrial protocolstack, and the protocol stack would not need to have knowledge of thatdetail. There could also be an overall directory mechanism that wouldallow the discovery of which IPv6 address corresponds to which entity.When the IP address was obtained, normal protocol mechanisms can beemployed to access the entity.

In another example, each IP address can refer to a “device within adevice” (from the CIP perspective, for example). Also, each IP addresscould refer to a separate CIP device model and CIP addressing spacewithin a single physical device. The CIP (or other protocol) addressingmodel can be modified to natively support using IP addresses and DNSnames to refer to specific objects, if desired. In yet anotheraddressing example, at 340 for other industrial networks, devicesconnected to the “other” network 340 can be native IPv6 devices, with anIPv6 stack. This can include having a router between an Ethernetnetwork, for example, and the “other” network 340. Another approach isto make the “other” network 340 appear as though it is an IPv6 networkto IPv6 devices. This can include having a gateway or translationfunction between the IPv6 and other devices. Thus, IPv6 router devicescan be employed between the Ethernet and “other” networks and/or also agateway device can be employed that can seamlessly connect an IPv6network with a non-IPv6 industrial network (making it appear as IPv6).

Referring to FIG. 4, an example system 400 illustrates communicationsaccording to an IPV6 protocol and domain name service addressing scheme.The system 400 is similar to the example system 300 described above withrespect to FIG. 3. In this case, logical addresses are employed forcommunications, where such addresses can be resolved from logical namesvia a DNS server or other type discovery component performing a look-upwhich is described in more detail below. In this example, an IPV6network 410 feeds an interface module 420 having two logical DNSaddresses. For instance, at 430, a feed conveyor is addressed that isresolved to a physical chassis. At 440, a system loader is addressedthat resolves to a different chassis name. From the interface 420, acontrol object heater communicated with at 450 and a control objectstirring device is addressed at 460. As can be appreciated, a pluralityof such chassis and devices can be so addressed. In another aspect,components can be provided to obtain a dynamic or auto-configured IPaddress and automatically cause a DNS system to be updated, associatingthe component's name with the newly obtained IP address. Such capabilitywould allow components to be referenced by name, replicated in differentlocations, without manually configuring and associating specific IPaddresses with names

Referring now to FIG. 5, a system 500 illustrates alternative networkingaspects. In this aspect, other communications protocols can be employedin conjunction with the global addressing schemes described above. Aplurality of controller services 510 through 530 interact with a globaladdress network cloud 540 via an XML-based protocol 550 that can beemployed with the industrial protocols described above. The protocol 550can be an open standard defined for use on a public communicationssystem such as the Internet. In one aspect, a Simple Object AccessProtocol (SOAP) 550 can be employed as a communications protocol for XMLWeb services. SOAP is an open specification that defines an XML formatfor messages between services. The specification can include describinghow to represent program data as XML and how to utilize SOAP to performRemote Procedure Calls. These optional parts of the specification areemployed to implement Remote Procedure Call (RPC)-style applications,wherein a SOAP message containing a callable function, and theparameters to pass to the function, is sent from a client such as acontrol system, and the server returns a message with the results of theexecuted function. Most current implementations of SOAP support RPCapplications since programmers who are familiar to COM or CORBAapplications understand the RPC style. SOAP also supports document styleapplications whereby the SOAP message is provided as a wrapper around anXML document. Document-style SOAP applications are very flexible,wherein a control system XML Web service can take advantage of thisflexibility to build controller services that may be difficult toimplement with RPC.

The controller services 510 through 530 can also employ an openinterface standard such as a Web Service Description Language (WSDL)illustrated at 560 through 568 in order to provide interactions with thecontroller services. In general, a WSDL file or interface is an XMLdocument that describes a set of SOAP messages and how the messages areexchanged. In other words, WSDL 560-564 is to SOAP what InterfaceDescription Language (IDL) is to CORBA or COM. Since WSDL is in XMLformat, it is readable and editable but in most cases, it is generatedand consumed by software. WSDL specifies what a request message containsand how the response message will be formatted in unambiguous notation.As an example, an I/O service can specify how inputs are to be requestedfrom the service and how outputs can be sent to the service in the formof a response. In another aspect, inputs can be requested from an inputservice, wherein the response is a confirmation that the inputs werereceived. Outputs can be sent to an output service in the form of arequest, wherein the response from the service is that the outputs werereceived. As can be appreciated, the controller services can be executedat various network layers in a control system where such layers areaddressable via the global and singular addressing schemes describeabove.

The system 500 can also include a discovery component 570, wherein thecontroller services 510-530 can be published and determined. In oneaspect, a Universal Discovery Description and Integration (UDDI) can beprovided at 570 that serves as a type of logical “phone” directory(e.g., “yellow pages,” “white pages,” “green pages”) describing Webservices. A UDDI directory entry is an XML file that describes acontroller system and the services it offers. There are generally threeparts to an entry in the UDDI directory. The “white pages” describe thecomponent offering the service: name, address, and so forth. The “yellowpages” include industrial categories based on standard taxonomies suchas the North American Industry Classification System and StandardIndustrial Classifications. The “green pages” describe the interface tothe service in enough detail for users to write an application to employthe Web service. The manner services are defined is through a UDDIdocument called a Type Model or tModel. In many cases, the tModelcontains a WSDL file that describes a SOAP interface to an XML Webservice, but the tModel is generally flexible enough to describe almostany kind of service. The UDDI directory also includes several options tosearch for the services to build remote applications. For example,searches can be performed for providers of a service in a specifiedgeographic location or for an entity of a specified type. The UDDIdirectory can then supply information, contacts, links, and technicaldata to enable determinations of which services to employ in a controlprocess. The discovery component 570 can be employed with a globaladdressing scheme such as Ethernet IPV6 for example to locate lowerlevel control elements such as the controller service 510-530.

FIG. 6 illustrates a process 600 for communicating over s singularaddress space. While, for purposes of simplicity of explanation, themethodology is shown and described as a series of acts, it is to beunderstood and appreciated that the methodology is not limited by theorder of acts, as some acts may occur in different orders and/orconcurrently with other acts from that shown and described herein. Forexample, those skilled in the art will understand and appreciate that amethodology could alternatively be represented as a series ofinterrelated states or events, such as in a state diagram. Moreover, notall illustrated acts may be required to implement a methodology asdescribed herein.

At 610, one or more controller service types and protocols are definedin accordance with open standards. As noted above, this can includeEthernet IPV6 protocols that communicate across industrial networks.Other protocols can include XML based protocols for interacting with theservice. The service types can be defined as a processing service, alogic service, an input and/or an output service, and a controllerinformation service, for example. As can be appreciated a plurality ofcontrol and communications objects can be defined. At 614, interfacesare defined in accordance with global or singular address space. Forexample, this can include interfaces that describe how control requestsand responses are processed by the control objects and how addresses aretransported across networks.

It is noted that other publicly available standards/protocols/servicesmay be employed. For example an enterprise service may be defined thatcoordinates different portions of a business or control process (e.g.,batch, quality, ERP) throughout various portions of an organization. Tofacilitate consistent batch quality, for example, a service can bedefined and offered which follows an international standard for modularbatch automation, such as defined by standard (S88, S95), which alsodefines models and terminology for identifying equipment capability andprocedures for producing batches. These procedures and capabilities canbe defined and offered by an associated service. These standards specifythe information flow between enterprise and manufacturing control. Thus,remote services can be offered that are modeled on these internationalstandards and operate to coordinate control processes from the plantfloor throughout the businesses that employ the control processes.

Proceeding to 622, service data is defined that describes data consumedby and produced by a respective service object. In general, XML can beemployed to define the data but other type data including industrialcontrol data can also be exchanged with the service. At 624, accessmodes can be defined for a service. This can include defining whether aservice or object is polled for data results, the service broadcastsdata after processing has been achieved, and/or the service isconfigured in a request and reply mode to exchange data in response to aspecific request to the service.

At 628, controller services or objects are located. As noted above, thiscan include polling a UDDI directory to determine the service andrespective interfaces. At 632, after a controller object has beenlocated across global address space, data is exchanged with the serviceto affect operations of a control process (e.g., automaticallyexchanging I/O data with I/O service to automatically perform remoteprocessing service). At 636, results are retrieved from a respectiveservice or control object in accordance with the access modes defined at624. For example, a processing service may poll a status service atperiodic intervals to retrieve plant floor status information that isaggregated from a plurality of network devices. At 640, one or morecontrol actions may be performed based upon the results retrieved from636. For example, an I/O service may energize an output device basedupon a processing result received from a processing service.

FIG. 7 illustrates an example IPV6 data packet 700 for addressingcontrol objects within industrial control systems. As illustrated, thedata packet 700 can include a destination Ethernet address 710, a sourceEthernet address 720, and an IPV6 header and payload portion 730. Ingeneral, a default maximum transmission unit (MTU) size for IPv6 packets700 on an Ethernet is 1500 octets. This size may be reduced by a RouterAdvertisement containing an MTU option which specifies a smaller MTU, orby manual configuration of each node. If a Router Advertisement receivedon an Ethernet interface has an MTU option specifying an MTU larger than1500, or larger than a manually configured value, that MTU option may belogged to system management or discarded.

In general, IPV6 is a new version of the Internet Protocol, designed asthe successor to IP version 4 (IPv4) [RFC-791]. IPv6 increases the IPaddress size from 32 bits to 128 bits, to support more levels ofaddressing hierarchy, a much greater number of addressable nodes, andsimpler auto-configuration of addresses. The scalability of multicastrouting is improved by adding a “scope” field to multicast addresses.And a new type of address called an “anycast address” is defined, usedto send a packet to any one of a group of nodes. Some IPv4 header fieldshave been dropped or made optional, to reduce the common-case processingcost of packet handling and to limit the bandwidth cost of the IPv6header. Changes in the way IP header options are encoded allows for moreefficient forwarding, less stringent limits on the length of options,and greater flexibility for introducing new options in the future. A newcapability is added to enable the labeling of packets belonging toparticular traffic “flows” for which the sender requests specialhandling, such as non-default quality of service or “real-time” service.Other extensions are provided to support authentication, data integrity,and (optional) data confidentiality.

A frame format for the packets 700 includes IPv6 packets that aretransmitted in standard Ethernet frames. The Ethernet header containsthe Destination and Source Ethernet addresses and the Ethernet typecode, which contains the value 86DD hexadecimal. The data field containsthe IPv6 header followed by the payload, and possibly padding octets tomeet the minimum frame size for the Ethernet link. An interfaceidentifier [AARCH] for an Ethernet interface is based on an EUI-64identifier [EUI64] derived from the interface's built-in 48-bit IEEE 802address. The EUI-64 can be formed as follows.

The EUI of the Ethernet address (the first three octets) becomes thecompany_id of the EUI-64 (the first three octets). The fourth and fifthoctets of the EUI are set to the fixed value FFFE hexadecimal. The lastthree octets of the Ethernet address become the last three octets of theEUI-64. The Interface Identifier is then formed from the EUI-64 bycomplementing the “Universal/Local” (U/L) bit, which is thenext-to-lowest order bit of the first octet of the EUI-64. Complementingthis bit will generally change a 0 value to a 1, since an interface'sbuilt-in address is expected to be from a universally administeredaddress space and have a globally unique value.

A universally administered IEEE 802 address or an EUI-64 is signified bya 0 in a U/L bit position, while a globally unique IPv6 InterfaceIdentifier is signified by a 1 in the corresponding position. Forexample, the Interface Identifier for an Ethernet interface whosebuilt-in address is, in hexadecimal, is 34-56-78-9A-BC-DE would be36-56-78-FF-FE-9A-BC-DE. A different MAC address set manually or bysoftware should not be used to derive the Interface Identifier. If sucha MAC address is used, its global uniqueness property should bereflected in the value of the U/L bit. An IPv6 address prefix used forstateless network auto-configuration [ACONF] of an Ethernet interfacehas a length of 64 bits.

FIG. 8 illustrates example Ethernet IPV6 address modes 800 forcommunicating with industrial control systems. In general, Ethernetaddressing can include local link addresses 810, unicast addressing 820,and multicast addressing 830. For Link-Local Addresses 810, an IPv6link-local address [AARCH] for an Ethernet interface is formed byappending the Interface Identifier to the prefix FE80::/64. For Unicastaddress mapping 820, a Source/Target Link-layer address option has thefollowing form when the link layer is Ethernet. These include optionfields specifying Type 1 for Source Link-layer address and Type 2 forTarget Link-layer address. A length can be specified in units of 8octets. The Ethernet Address is a 48 bit Ethernet IEEE 802 address, incanonical bit order. This is the address the interface currentlyresponds to, and may be different from the built-in address used toderive the Interface Identifier.

With respect to multicast address mapping 830, an IPv6 packet with amulticast destination address DST, consisting of the sixteen octetsDST[1] through DST[16], is transmitted to the Ethernet multicast addresswhose first two octets are the value 3333 hexadecimal and whose lastfour octets are the last four octets of DST. In general, there may besome differences with older version of Ethernet. The following arepossible functional differences between older versions such as anAddress Token, which was a node's 48-bit MAC address, is replaced withthe Interface Identifier, which is 64 bits in length and based on theEUI-64 format [EUI64]. An IEEE-defined mapping exists from 48-bit MACaddresses to EUI-64 form. A prefix used for stateless auto-configurationis 64 bits long rather than 80. The link-local prefix is shortened to 64bits.

What has been described above includes various exemplary aspects. It is,of course, not possible to describe every conceivable combination ofcomponents or methodologies for purposes of describing these aspects,but one of ordinary skill in the art may recognize that many furthercombinations and permutations are possible. Accordingly, the aspectsdescribed herein are intended to embrace all such alterations,modifications and variations that fall within the spirit and scope ofthe appended claims. Furthermore, to the extent that the term “includes”is used in either the detailed description or the claims, such term isintended to be inclusive in a manner similar to the term “comprising” as“comprising” is interpreted when employed as a transitional word in aclaim.

1. An industrial communications system, comprising: a global addressprotocol that can be employed to communicate with local or remotenetworks; an industrial protocol adapted to interface with the globaladdress protocol; and at least one network component that communicateswith one or more control components via the industrial protocol and inaccordance with an address supplied by the global address protocol. 2.The system of claim 1, the global address protocol is an IPV6 protocol.3. The system of claim 1, the control components are associated with aprogrammable logic controller, a communications module, an input module,an output module or a network component.
 4. The system of claim 2, theglobal address protocol is an Ethernet IPV6 protocol.
 5. The system ofclaim 1, the industrial protocol is employed between control systems andincludes at least one of a Common Industrial Protocol (CIP) or aprotocol associated with ModBus.
 6. The system of claim 1, furthercomprising one or more control objects that are assigned an address fromthe global address protocol.
 7. The system of claim 6, furthercomprising an interface card that responds to each of the controlobjects within the card's scope and supplies routing information toenable a message to reach the control objects using the global addressprotocol.
 8. The system of claim 1, further comprising a Domain NameService (DNS) server that maps user-assigned names to control objects.9. The system of claim 8, the names are arranged into a hierarchy thatcorresponds to a problem description or a physical domain.
 10. Thesystem of claim 8, the control objects have multiple addresses, at leastone to indicate a physical location and at least one other address toindicate a fiction in a logical description of a user's factory orenvironment.
 11. The system of claim 9, further comprising a userinterface to manage the hierarchy or component to obtain dynamic orauto-configured Internet Protocol address.
 12. The system of claim 1,further comprising one or more network layers and one or more controllayers that employ the global address protocol, the respective layershaving one or more communications or control components per layer. 13.The system of claim 1, further comprising a component to send a messageutilizing the global address protocol from one system to another systememploying an industrial protocol.
 14. The system of claim 1, furthercomprising a network component that employs a single addressing mode toaddress higher level network components and lower level controlcomponents.
 15. The system of claim 14, further comprising one or morenested control objects that are assigned addresses from the globaladdress protocol.
 16. The system of claim 1, further comprising aninterface to assign logical factory names that are mapped to the globaladdress protocol.
 17. The system of claim 1, further comprising a SimpleObject Access Protocol to facilitate network communications.
 18. Thesystem of claim 1, further comprising a Web Service Description Language(WSDL) component to provide interactions with one or more controllerservices.
 19. The system of claim 1, further comprising a UniversalDiscovery Description and Integration (UDDI) component to facilitatelocating network components.
 20. The system of claim 1, furthercomprising at least one of a processing service, a logic service, aninput service, an output service, and a controller information service,that are located via the global address protocol.
 21. The system ofclaim 20, further comprising a protocol to facilitate communications tointeract with an S88 or S95 control model.
 22. A computer readablemedium having a data structure stored thereon to facilitate industrialcontrol communications, comprising: a first data field to define aglobal address protocol; a second data field to specify a factorynetwork protocol; and a third data field to specify a control objectdestination that is based in part on the global address protocol. 23.The computer readable medium of claim 22, further comprising a fourthdata field to specify at least one source location for a message.
 24. Anindustrial control communications method, comprising: assigning a globalnetwork address to at least one control object; locating the controlobject on an industrial control network; and communicating with thecontrol object with the global network address.
 25. The method of claim24, further comprising employing a domain name service to assign logicalnames in accordance with the global network address.
 26. The method ofclaim 24, the global network address conforms to an IPV6 standard. 27.The method of claim 24, further comprising assigning IPv6 addresses tospecific objects within an industrial protocol.
 28. The method of claim24, further comprising assigning IPv6 addresses a control function. 29.The method of claim 24, further comprising assigning IPv6 addresses to atag, (named data), a routine, or an entity associated with a factorymodel.
 30. The method of claim 24, further comprising associating atleast one protocol stack with a single application addressing space. 31.The method of claim 24, further comprising defining a directory thatallows discovery of a respective IPv6 address that corresponds to atleast one entity.
 32. The method of claim 24, further comprisingdefining an Internet Protocol (IP) address that refers to a devicewithin a device.
 33. The method of claim 32, further comprising definingthe IP address to refer to a separate device model and addressing spacewithin a single physical device.
 34. The method of claim 24, furthercomprising employing an IPv6 router or an IPv6 gateway device tocommunicate between at least two different networks or network devices.35. An industrial control communications systems, comprising: means forassigning addresses from a global address space; means for interfacingto a control network; and means for communicating to the control networkvia the addresses from the global address space.
 36. The system of claim35, further comprising means for locating control objects according to alogical object description.